7 ms·

It's been 500 years since California has been this dry

70 points by JohnHammersley 11y ago

SCAQTony 11y ago
Then we are due for an ArkStorm or Atmospheric River. From the USGS: "...This document summarizes the next major public project for MHDP, a winter storm scenario called ARkStorm (for Atmospheric River 1,000). Experts have designed a large, scientifically realistic meteorological event followed by an examination of the secondary hazards (for example, landslides and flooding), physical damages to the built environment, and social and economic consequences. The hypothetical storm depicted here would strike the U.S. West Coast and be similar to the intense California winter storms of 1861 and 1862 that left the central valley of California impassible. The storm is estimated to produce precipitation that in many places exceeds levels only experienced on average once every 500 to 1,000 years." http://pubs.usgs.gov/of/2010/1312/ http://pubs.usgs.gov/of/2010/1312/
- anigbrowl 11y ago
  Great find, thanks. The ARkStorm has several public policy implications: (1) An ARkStorm raises serious questions about the ability of existing federal, state, and local disaster planning to handle a disaster of this magnitude. (2) A core policy issue raised is whether to pay now to mitigate, or pay a lot more later for recovery.[...] I think we can all guess what the answer to #2 has been since :-(
- nkurz 11y ago
  An interesting report, but is there any reason to conclude that "we are due"? If the lack of rain is random (like flipping a fair coin), the expected time to event would still be 1000 years. Believing that "heads" is more likely after a string of "tails" is the classic Gambler's Fallacy: https://en.wikipedia.org/wiki/Gambler%27s_fallacy https://en.wikipedia.org/wiki/Gambler%27s_fallacy If on the other hand the current drought is caused by a change in climate, there is even less reason to believe that we are due for a gigantic amount of rain. If the coin is biased (bent) logic would conclude that one should bet that recent performance _is_ an indicator of future performance. While it's not impossible for alternation to be most likely, it requires some physical process that would explain it. Interestingly, weather in the Central California often does follow multi-week cycles, with hot inland weather leading to rising air at the coast, leading to fog flowing inland, leading to a cooldown[1]. But I don't know of any process that would explain this for century scale rainfall. Do you? [1] This article offers an explanation of the "fog cycle", but with the cautious wording "Until recent years, the conventional explanation for the fog’s behavior was a simple one". I wonder if there is now better knowledge: https://baynature.org/articles/cutting-through-the-fog/ https://baynature.org/articles/cutting-through-the-fog/
  - 001sky 11y ago
    Just FYI, Utah (Desert) had the 2nd largest month of rain in itsrecorded history already this year. All that says is armchair weather prediction is silly.
  - cbennett 11y ago
    "An interesting report, but is there any reason to conclude that "we are due"?" Yes, El Nino, which may bring torrents of rain this winter to the US west coast. The combination with epic drought will be disastrous, whether or not if fulfills the mythic criterion of an "ArkStorm' FYI: occurrence of rain or lack thereof is not like flipping a coin; this is more like a chaotic system with non-linear patterns evolving; once we see a large-scale pattern that occurs, and we identify it recurring through time such as El Nino, we can spot its tell-tale signs ahead of time and warn folks that worse may be on the way. Nevertheless, there are no guarantees, all we can do is wait and watch- But it certainly changes our Prior to know about these recurrent global-weather-scale patterns. http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-150913093902800.html http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-...
    - nkurz 11y ago
      occurrence of rain or lack thereof is not like flipping a coin Yes, absolutely. El Nino is a fine reason to believe that the pattern will change. At a decadal scale, there is reason to believe that recent drought is a predictor of future rain. My point though was that there was not (a priori) a reason to believe that "It's been 500 years since California has been this dry" would imply "we are due" for a 1000 year storm.
thaumaturgy 11y ago
Yeah, everything I read on the current trends in California's climate just keeps sounding more and more dire. I was stuck inside all weekend due in large part to thick smoke and ash; I don't want to live in a drought or on the cusp of a drought every year for the foreseeable future and I don't think it's real smart to breathe smoke from wildfires year after year either. California could mitigate a lot of this, and probably will, eventually. But, it's only been about 6 years since the CRU email leaks led to it being dubbed "climategate" and a whole bunch of people loudly declared that it was proof that AGW was a vast climate scientist conspiracy. There's going to be a tremendous amount of resistance from all angles to any attempts to mitigate the effects of the climate in California. So I started looking for work out of state a while ago, and will keep looking. Nice place, but it would be dumb of me to stay here.
- nkurz 11y ago
  California could mitigate a lot of this, and probably will, eventually. ... There's going to be a tremendous amount of resistance from all angles to any attempts to mitigate the effects of the climate in California. Where do you see the resistance coming from? The timescale here is interesting, because "driest in 500 years" implies that although this particular instance might be caused by human activity, that we are still in the range of natural variability. I'd guess that many people who fear upending civilization to avoid CO2 production would agree that a reliable water supply is a priority. Would concentrating on the issue (less water than demand) rather than the causes (anthropogenic or not) make it more likely for mitigation efforts to succeed?
  - thaumaturgy 11y ago
    > Where do you see the resistance coming from? Environmentalists don't want more dams constructed; agriculture doesn't want more water use regulation; industry doesn't want tighter environmental (or water) regulations; residents aren't going to be able to cut back on water usage much more; automobile manufacturers don't want further emissions cuts. Every single interest group wants to point to another interest group and say, "this situation is their fault, make them fix it instead." I think a better question is, where do you not see resistance coming from? > we are still in the range of natural variability And does that make this a more comfortable living situation for you? > I'd guess that many people who fear upending civilization to avoid CO2 production would agree that a reliable water supply is a priority. It's true that the recent and continuing decline of carbon dioxide emissions (https://en.wikipedia.org/wiki/Greenhouse_gas#/media/File:Yearly_trends_in_annual_regional_carbon_dioxide_emissions_from_fuel_combustion_between_1971_and_2009.png https://en.wikipedia.org/wiki/Greenhouse_gas#/media/File:Yea...) is "upending civilization" -- we have never been worse off, as a species, than we are now -- but why we could expect those people to agree on how to get a reliable water supply is a mystery to me, given that they can't even be expected to agree on what the problem is. > Would concentrating on the issue (less water than demand) rather than the causes (anthropogenic or not) make it more likely for mitigation efforts to succeed? Well, I dunno, I guess. If people refuse to address the causes -- which, even in the face of overwhelming supporting evidence, they seem likely to do -- then I suppose the only remaining option is to decrease demand down to levels that can be supported by the relatively meager amounts of precipitation across the state. Which, again, makes California sound like a pretty nice place to be from.
jobu 11y ago
uBlock didn't allow the new site design at all, and I didn't really like it either. Here's the link to their "classic" view of the article: http://www.washingtonpost.com/news/energy-environment/wp/2015/09/14/scientists-say-its-been-500-years-since-california-was-this-dry/ http://www.washingtonpost.com/news/energy-environment/wp/201...
- jrapdx3 11y ago
  Yeah I noticed that too. However, with current Firefox the "Reader View" worked well, and I was able to read the article just fine.
paulhauggis 11y ago
It must be global warming
olivermarks 11y ago
It's the last thing on most people's minds right now with the drought, but an ARkStorm style event this winter (or even just heavy persistent rain and flooding) could be disastrous for the Sacramento delta levies, which are in a very delicate state. Hoping for a slow and steady refill of the reservoirs this winter...
- matheweis 11y ago
  I hate to be the harbinger, but it's shaping up for just that kind of scenario: "El Nino set to be strongest ever" http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-150913093902800.html http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-...
  - gdubs 11y ago
    The question is whether the "Ridiculously Resilliant Ridge" -- the name for the blob of warm water sitting in the pacific -- will continue to prevent the moisture from reaching the costal states, as it has been doing for some time now.
- pdkl95 11y ago
  > Sacramento delta levies Hmm... as someone currently living in Woodland - which is right on the other side of the causeway across the immediate spill area for those levies - I'm wondering how safe this winter will be. Woodland is an old town, so it's on slightly higher ground than some of the surrounding areas, but apparently that may not matter.
  - nicklaf 11y ago
    As a Davis resident, I was curious to get a more detailed map of the flood areas for a hypothetical ARkStorm than the one provided by the Wikipedia article on the topic [1]. To that end, I created an animation, morphing between a google maps screen-cap, and the USGS map of the flood areas [2]. I didn't get the alignment just right, but from the look of it Woodland would appear to be underwater (at least, according to this USGS flood model). That all said, is there really any evidence that a strong El Niño has anything at all to do with an ARkStorm? The Wikiepdia article on The Great Flood of 1862 [3] has this to say: "The weather pattern that caused this flood was not from an El Nino [sic]". [1] https://en.wikipedia.org/wiki/ARkStorm#/media/File:California_ARkStorm_Flood_Areas.jpg https://en.wikipedia.org/wiki/ARkStorm#/media/File:Californi... [2] http://imgur.com/cMScw5G http://imgur.com/cMScw5G [3] https://en.wikipedia.org/wiki/Great_Flood_of_1862 https://en.wikipedia.org/wiki/Great_Flood_of_1862
craigyk 11y ago
Driest surface in 500 years. I wonder how long it's been since the aquifers have been at their current levels.
kevindeasis 11y ago
Here is a guy driving away from Anderson Spring fire: https://www.youtube.com/watch?v=0lVPB3HI9Wg https://www.youtube.com/watch?v=0lVPB3HI9Wg
jrapdx3 11y ago
The drought is affecting several western states, including Oregon where I live. The severity here isn't (yet) as extreme as in California, but it definitely is having palpable detrimental effects on water supply and agriculture in parts of Oregon. There's been ongoing study of this weather phenomenon by various research institutions including Oregon State Univ. Apparently a "blob" of warmer-than-usual water in the northern Pacific is associated with the drought condition. It's uncertain if it's connected to global warming--that's a subject of ongoing study. There's a lot more information here: http://www.climateprediction.net/new-climatology-results-for-western-us-drought-experiment/ http://www.climateprediction.net/new-climatology-results-for... The graphic data presentation is quite interesting, e.g., comparing California, Oregon and Washington. The research relies on distributed computing to run experimental climate models, some HN readers might be interested in participating.

Then we are due for an ArkStorm or Atmospheric River. From the USGS: "...This document summarizes the next major public project for MHDP, a winter storm scenario called ARkStorm (for Atmospheric River 1,000). Experts have designed a large, scientifically realistic meteorological event followed by an examination of the secondary hazards (for example, landslides and flooding), physical damages to the built environment, and social and economic consequences. The hypothetical storm depicted here would strike the U.S. West Coast and be similar to the intense California winter storms of 1861 and 1862 that left the central valley of California impassible. The storm is estimated to produce precipitation that in many places exceeds levels only experienced on average once every 500 to 1,000 years." http://pubs.usgs.gov/of/2010/1312/ http://pubs.usgs.gov/of/2010/1312/

anigbrowl 11y ago
Great find, thanks. The ARkStorm has several public policy implications: (1) An ARkStorm raises serious questions about the ability of existing federal, state, and local disaster planning to handle a disaster of this magnitude. (2) A core policy issue raised is whether to pay now to mitigate, or pay a lot more later for recovery.[...] I think we can all guess what the answer to #2 has been since :-(
nkurz 11y ago
An interesting report, but is there any reason to conclude that "we are due"? If the lack of rain is random (like flipping a fair coin), the expected time to event would still be 1000 years. Believing that "heads" is more likely after a string of "tails" is the classic Gambler's Fallacy: https://en.wikipedia.org/wiki/Gambler%27s_fallacy https://en.wikipedia.org/wiki/Gambler%27s_fallacy If on the other hand the current drought is caused by a change in climate, there is even less reason to believe that we are due for a gigantic amount of rain. If the coin is biased (bent) logic would conclude that one should bet that recent performance _is_ an indicator of future performance. While it's not impossible for alternation to be most likely, it requires some physical process that would explain it. Interestingly, weather in the Central California often does follow multi-week cycles, with hot inland weather leading to rising air at the coast, leading to fog flowing inland, leading to a cooldown[1]. But I don't know of any process that would explain this for century scale rainfall. Do you? [1] This article offers an explanation of the "fog cycle", but with the cautious wording "Until recent years, the conventional explanation for the fog’s behavior was a simple one". I wonder if there is now better knowledge: https://baynature.org/articles/cutting-through-the-fog/ https://baynature.org/articles/cutting-through-the-fog/
- 001sky 11y ago
  Just FYI, Utah (Desert) had the 2nd largest month of rain in itsrecorded history already this year. All that says is armchair weather prediction is silly.
- cbennett 11y ago
  "An interesting report, but is there any reason to conclude that "we are due"?" Yes, El Nino, which may bring torrents of rain this winter to the US west coast. The combination with epic drought will be disastrous, whether or not if fulfills the mythic criterion of an "ArkStorm' FYI: occurrence of rain or lack thereof is not like flipping a coin; this is more like a chaotic system with non-linear patterns evolving; once we see a large-scale pattern that occurs, and we identify it recurring through time such as El Nino, we can spot its tell-tale signs ahead of time and warn folks that worse may be on the way. Nevertheless, there are no guarantees, all we can do is wait and watch- But it certainly changes our Prior to know about these recurrent global-weather-scale patterns. http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-150913093902800.html http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-...
  - nkurz 11y ago
    occurrence of rain or lack thereof is not like flipping a coin Yes, absolutely. El Nino is a fine reason to believe that the pattern will change. At a decadal scale, there is reason to believe that recent drought is a predictor of future rain. My point though was that there was not (a priori) a reason to believe that "It's been 500 years since California has been this dry" would imply "we are due" for a 1000 year storm.

thaumaturgy 11y ago

Yeah, everything I read on the current trends in California's climate just keeps sounding more and more dire. I was stuck inside all weekend due in large part to thick smoke and ash; I don't want to live in a drought or on the cusp of a drought every year for the foreseeable future and I don't think it's real smart to breathe smoke from wildfires year after year either. California could mitigate a lot of this, and probably will, eventually. But, it's only been about 6 years since the CRU email leaks led to it being dubbed "climategate" and a whole bunch of people loudly declared that it was proof that AGW was a vast climate scientist conspiracy. There's going to be a tremendous amount of resistance from all angles to any attempts to mitigate the effects of the climate in California. So I started looking for work out of state a while ago, and will keep looking. Nice place, but it would be dumb of me to stay here.

nkurz 11y ago
California could mitigate a lot of this, and probably will, eventually. ... There's going to be a tremendous amount of resistance from all angles to any attempts to mitigate the effects of the climate in California. Where do you see the resistance coming from? The timescale here is interesting, because "driest in 500 years" implies that although this particular instance might be caused by human activity, that we are still in the range of natural variability. I'd guess that many people who fear upending civilization to avoid CO2 production would agree that a reliable water supply is a priority. Would concentrating on the issue (less water than demand) rather than the causes (anthropogenic or not) make it more likely for mitigation efforts to succeed?
- thaumaturgy 11y ago
  > Where do you see the resistance coming from? Environmentalists don't want more dams constructed; agriculture doesn't want more water use regulation; industry doesn't want tighter environmental (or water) regulations; residents aren't going to be able to cut back on water usage much more; automobile manufacturers don't want further emissions cuts. Every single interest group wants to point to another interest group and say, "this situation is their fault, make them fix it instead." I think a better question is, where do you not see resistance coming from? > we are still in the range of natural variability And does that make this a more comfortable living situation for you? > I'd guess that many people who fear upending civilization to avoid CO2 production would agree that a reliable water supply is a priority. It's true that the recent and continuing decline of carbon dioxide emissions (https://en.wikipedia.org/wiki/Greenhouse_gas#/media/File:Yearly_trends_in_annual_regional_carbon_dioxide_emissions_from_fuel_combustion_between_1971_and_2009.png https://en.wikipedia.org/wiki/Greenhouse_gas#/media/File:Yea...) is "upending civilization" -- we have never been worse off, as a species, than we are now -- but why we could expect those people to agree on how to get a reliable water supply is a mystery to me, given that they can't even be expected to agree on what the problem is. > Would concentrating on the issue (less water than demand) rather than the causes (anthropogenic or not) make it more likely for mitigation efforts to succeed? Well, I dunno, I guess. If people refuse to address the causes -- which, even in the face of overwhelming supporting evidence, they seem likely to do -- then I suppose the only remaining option is to decrease demand down to levels that can be supported by the relatively meager amounts of precipitation across the state. Which, again, makes California sound like a pretty nice place to be from.

jobu 11y ago

uBlock didn't allow the new site design at all, and I didn't really like it either. Here's the link to their "classic" view of the article: http://www.washingtonpost.com/news/energy-environment/wp/2015/09/14/scientists-say-its-been-500-years-since-california-was-this-dry/ http://www.washingtonpost.com/news/energy-environment/wp/201...

jrapdx3 11y ago
Yeah I noticed that too. However, with current Firefox the "Reader View" worked well, and I was able to read the article just fine.

paulhauggis 11y ago

It must be global warming

olivermarks 11y ago

It's the last thing on most people's minds right now with the drought, but an ARkStorm style event this winter (or even just heavy persistent rain and flooding) could be disastrous for the Sacramento delta levies, which are in a very delicate state. Hoping for a slow and steady refill of the reservoirs this winter...

matheweis 11y ago
I hate to be the harbinger, but it's shaping up for just that kind of scenario: "El Nino set to be strongest ever" http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-150913093902800.html http://www.aljazeera.com/news/2015/09/el-nino-set-strongest-...
- gdubs 11y ago
  The question is whether the "Ridiculously Resilliant Ridge" -- the name for the blob of warm water sitting in the pacific -- will continue to prevent the moisture from reaching the costal states, as it has been doing for some time now.
pdkl95 11y ago
> Sacramento delta levies Hmm... as someone currently living in Woodland - which is right on the other side of the causeway across the immediate spill area for those levies - I'm wondering how safe this winter will be. Woodland is an old town, so it's on slightly higher ground than some of the surrounding areas, but apparently that may not matter.
- nicklaf 11y ago
  As a Davis resident, I was curious to get a more detailed map of the flood areas for a hypothetical ARkStorm than the one provided by the Wikipedia article on the topic [1]. To that end, I created an animation, morphing between a google maps screen-cap, and the USGS map of the flood areas [2]. I didn't get the alignment just right, but from the look of it Woodland would appear to be underwater (at least, according to this USGS flood model). That all said, is there really any evidence that a strong El Niño has anything at all to do with an ARkStorm? The Wikiepdia article on The Great Flood of 1862 [3] has this to say: "The weather pattern that caused this flood was not from an El Nino [sic]". [1] https://en.wikipedia.org/wiki/ARkStorm#/media/File:California_ARkStorm_Flood_Areas.jpg https://en.wikipedia.org/wiki/ARkStorm#/media/File:Californi... [2] http://imgur.com/cMScw5G http://imgur.com/cMScw5G [3] https://en.wikipedia.org/wiki/Great_Flood_of_1862 https://en.wikipedia.org/wiki/Great_Flood_of_1862

craigyk 11y ago

Driest surface in 500 years. I wonder how long it's been since the aquifers have been at their current levels.

kevindeasis 11y ago

Here is a guy driving away from Anderson Spring fire: https://www.youtube.com/watch?v=0lVPB3HI9Wg https://www.youtube.com/watch?v=0lVPB3HI9Wg

jrapdx3 11y ago

The drought is affecting several western states, including Oregon where I live. The severity here isn't (yet) as extreme as in California, but it definitely is having palpable detrimental effects on water supply and agriculture in parts of Oregon. There's been ongoing study of this weather phenomenon by various research institutions including Oregon State Univ. Apparently a "blob" of warmer-than-usual water in the northern Pacific is associated with the drought condition. It's uncertain if it's connected to global warming--that's a subject of ongoing study. There's a lot more information here: http://www.climateprediction.net/new-climatology-results-for-western-us-drought-experiment/ http://www.climateprediction.net/new-climatology-results-for... The graphic data presentation is quite interesting, e.g., comparing California, Oregon and Washington. The research relies on distributed computing to run experimental climate models, some HN readers might be interested in participating.